38 lines
572 B
Markdown
38 lines
572 B
Markdown
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# Question 1388
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Good morning! Here's your coding interview problem for today.
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This problem was asked by Apple.
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Implement a queue using two stacks. Recall that a queue is a FIFO (first-in, first-out) data structure with the following methods: enqueue, which inserts an element into the queue, and dequeue, which removes it.
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## Implementation
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```
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Command: Push(1,2,3)
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LHS | 3 2 1
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RHS |
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Command: Pop() -> Expect val of 1
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if RHS is not empty
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return RHS.pop()
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while LHS is not empty:
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RHS.push(LHS.pop())
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LHS |
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RHS | 1 2 3
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return RHS.pop()
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RHS | 2 3
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```
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